1. Field of the Invention
The invention concerns an anal retractor with retractor valves guided for movement apart.
2. Related Art of the Invention
Anal retractors are used in order to dilate the anal canal for medical interventions and examinations. These anal retractors include retractor valves, which are introduced into the anal canal and then are moved apart for dilation of the anal canal.
In one known embodiment two retractor valves are provided, which are spread apart using a scissors grip. Therewith only a comparatively small dilation of the anal canal is possible. Further, an anal retractor with two retractor valves is known, in which the one retractor valve is displaceable on a guide rail provided upon the other retractor valve. Therewith the retractor blades can, on the one hand, be spread further apart, the spreading of the anal canal occurs however only in diametrically opposed directions, so that the access cross-section is not optimally enlarged. Finally, an anal retractor is known in which two retractor valves can be moved apart via a scissors grip and wherein a third retractor valve is provided pivotable about a plane perpendicular to the pivot axis of the scissors grip. The three retractor valves produce a larger access cross-section of the dilated anal canal. The access cross-section is however asymmetric in this case, and is essentially determined by the diametric spreading movement of the scissors grip.